Cassettes for use in tape recorders can be easily mounted and operated as compared with those disposed on open reels, and find an extensive use among the blind. As is well recognized, during a record or playback operation, the magnetic tape in a tape cassette is run in one direction until the tape end is reached, whereupon the cassette must be removed from the tape recorder to invert it before it is loaded again to be run in the opposite direction. The front and rear sides of a tape cassette is usually designated by indicia such as A, B (see FIGS. 1 and 2) or 1, 2, which are printed on a label applied to both the front and rear sides of the cassette.
However, these indicia cannot be recognized by the blind. To overcome this difficulty, there has been a proposal to emboss either one of the indicia applied to the label in order to permit a distinction of the front from the rear surface. However, with a tape cassette of a miniature size, the indicia themselves will be reduced in size and an easily recognizable indicium cannot be formed. In addition, with a tape cassette of a miniature size, various openings such as openings for fitting the drive shafts of hubs of tape reels, a capstan aperture and positioning pin apertures of the cassette are dispersed throughout the both surfaces, so that it becomes difficult to make a positive distinction between such openings or apertures and the embossed indicia.
In addition, the playing time or the tape running speed depends on the tape contained in a cassette, and an indication of the kind of the tape is usually given on the label applied to the cassette. Thus, providing a distinction between the front and rear sides of the cassette by tactile response alone is not sufficient for blind use. Therefore, it is apparent that there has been a need for a tape cassette which is adapted for blind use.